Bluetooth Core Specification
Bluetooth is a communication technology that is documented in the Bluetooth Core Specification that standardizes it.
This document is maintained by the Bluetooth Special Interest Group, Inc. or Bluetooth SIG, a private association of companies interested in the technology. The members of this group are responsible for the development of Bluetooth.
As the technology evolves, the Bluetooth SIG publishes new versions of the Bluetooth Core Specification in the specifications section of SIG’s website. It should be noted that these specifications have a Status indicating whether that specification is fit for use or already obsolete.
The specification, in its various versions, contains all the necessary information about the protocol to develop a device that can interoperate with other Bluetooth devices. This includes information about physical transport, the lowest layers of the protocol, up to the transport of application-level data. For this reason, it is a very extensive and rather complex specification.
Often, in this methodology, you will find references to the Bluetooth Core Specification document where you can find more detailed information on the referenced topics.
Other Bluetooth SIG documents
Besides the core protocol specification, the SIG also publishes other documents of interest such as the Bluetooth Assigned Numbers where numerical values and constants used in Bluetooth are listed, such as manufacturer identifiers or constants for the identification of Bluetooth versions.
The GATT Specification Supplement is also of special interest, as it contains all the definitions of the GATT characteristics and other descriptors of Bluetooth services.